Observing Bess Beetles or Millipedes: How Do The Compare with the Pill Bugs?
In this lesson, students and teachers will encounter a woodland organism with which they are likely unfamiliar or less familiar than with the previous organisms. It should raise students' awareness that there are many more organisms in the world than they have ever seen. The objectives remain similar with a new organism to observe.
INQA Scientific investigations involve asking and trying to answer a question about the natural world by making and recording observations.
INQC Scientists develop explanations, using recorded observations (evidence).
INQD Scientists report on their investigations to other scientists, using drawings and words.
INQF All scientific observations must be reported honestly and accurately.
SYSA Living and nonliving things are made of parts. People give names to the parts that are different from the name of the whole object, plant, or animal.
LS1B All plants and animals have various external parts.
LS1C The parts of a plant or animal appear different under a magnifier compared with the unaided eye.
LS2A There are different kinds of natural areas, or habitats, where many different plants and animals live together.
LS3A Some things are alive and others are not.
LS3B There are many different types of living things on Earth. Many of them are classified as plants or animals.
LS3C External features of animals and plants are used to classify them into smaller groups.
- Student will observe, draw and describe pill bugs to understand characteristics of animal organisms.
- Students will develop an understanding of what pill bugs and other animals need in order to live
- Teachers should be aware that they will receive either millipedes or Bess beetles and should study the background that pertains to their organism. This lesson looks long but it is just because background and procedure is given for each organism. Only one will be used by teachers.
- You may want overhead copies of figure 10-1 or 10-2 in the Organisms Teacher’s Guide to show students the different body parts of these organisms up close. They can be hard to discern in observation.
- You will need tree bark or wood chunks for the beetles (such as may be found under playground equipment), or lettuce and mushrooms for the millipedes to eat.
- BEETLES: Keep the wood chunks moist so beetles can chew them.
- MILLIPEDES: These guys are amazing escape artists and fast travelers. Alert your staff to watch for millipedes curled up and looking like a 1" diameter, brown button laying in the halls or classrooms in the mornings!
The Bess beetle in the terrarium
Students should always label diagrams
in the science notebook.
- MILLIPEDES: Have students feed each millipede when out on the newsprint to better observe how they eat.
- MILLIPEDES: Students may be more comfortable holding millipedes with plastic gloves. They are quite harmless but sometimes release a fluid from "stink glands" when frightened. It isn't really too smelly. They will usually "play dead" when frightened and when being held.
- BEETLES: To pick up the Bess beetle gently place finger and thumb between the first and second pair of legs. Try not to pull the beetle off of yourself or another person. Let it crawl off.
- Each student should try to hold the beetle or millipede but don’t force the issue if a student is particularly reluctant.
- BEETLES: Prepare students for the fact that Bess beetles tickle when they crawl on your hand. They feel kind of like Velcro.
- BEETLES: Sometimes the Bess beetles make a hissy-squeaky noise so prepare student to prevent startled bug dropping!
- Get comfortable with the animal, whichever you have. If you are comfortable with the animal, students will be more comfortable with observing and touching them. Try to get used to touching these organisms. To pick up the Bess beetle gently place finger and thumb between the first and second pair of legs. Try not to pull the beetle off of yourself or another person; let it crawl off. You may be more comfortable holding millipedes with plastic gloves. They are quite harmless but sometimes release a fluid from "stink glands" when frightened. It isn't really too smelly. They will usually "play dead" when frightened and when being held.
- As in other lessons if the lesson needs to be split into two parts, a stopping point that works well is before beginning the Final Activities, which are the after observation, discussion and completion of the class Venn diagram or box & T-chart.
- As with previous lessons, the Final Activities section leads students through a class discussion of what characteristics they have observed in their new organism. Teachers need to facilitate discussion of how the pill bugs and millipede/Bess beetle are similar and different.
- Three categories of assessment are possibilities.
- Individual student products (the recording sheets or science notebook).
- Class products-charts, Venn diagrams/ diagrams/ box & T-charts, discussion.
- Teacher observation.
- A good way to keep track of comments and observations as students work is to do a "Clipboard Cruise" as students work. Walk around with your clipboard and briefly note student comments and observations. Be sure to note who makes the comments. This can help stimulate discussion later as the teacher can bring up what s/he heard during the lesson.
- Students could complete their own observation organizer and, as a second writing step, write a short paragraph using these as a scaffold. It can be overkill to have them use these at every lesson so choose those lessons which seem to be the richest source of writing.
- The poem "I Like Bugs" by Margaret Wise Brown makes a great choral reading. Students can practice it many times until it is memorized. Then use it as a chant while waiting in the lunch line or lining up to go out for recess or home.
- The longest millipedes are about 16.5 cm (6.5 in.). Have students show an estimate of how long that would be using familiar references such as the length of a small paper clip. Then have them measure out that distance on a pipe cleaner, yarn or line on paper. Then estimate the length of their millipede and measure it (as well as they can) and measure that distance on a pipe cleaner, yarn or a line on paper to compare the two.